Health management is a modem phrase in the industry for engine and/or equipment condition monitoring and maintenance planning, especially in the aerospace industry. In a historical perspective, Condition Monitoring System (CMS) is a generally accepted term for a ground-based (remote) or an on-board system (local) that performs some level of condition monitoring and health management. The scope of a CMS typically includes failure alert, detection, and isolation. Maintenance planning is performed by some ground-based systems and is mostly concerned with scheduled inspections and time-based repairs, or On-Condition Maintenance (OCM), i.e., a part is replaced only for cause.
With the recently emphasis on Reliability-Centered Maintenance (RCM), the goal of health management has been focused on implementing a systematic process of determining the maintenance requirements of a physical asset, which may be an entire piece of equipment such as an engine or a single part of the equipment/engine, to ensure its readiness, performance, and operability. To determine maintenance requirements effectively, the identification of failures and the prediction of failure progressions are essential; hence the Prognostics and Health Management (PHM) philosophy has also been emphasized recently in industries such as the aerospace industry. The various functions of health management are illustrated in FIG. 1.
The purpose of equipment health management is to realize significant benefits in operations planning and reduced cost of ownership. To realize these benefits, the various health management functions, as illustrated in FIG. 1, must be efficiently integrated and timely updated with new information. Since 1985, the U.S. Air Force has been using a computer program to facilitate engine health management. This program, known as the Comprehensive Engine Trending and Diagnostic System (CETADS), incorporates graphical user interface based software to help the Air Force perform data trending and diagnostic functions for its engine fleets. As the primary tool for data-driven engine health management CETADS has many limitations that have prevented it from realizing the full potential benefits of health management. Among these limitations are:                The program has too low an automation level. The program needs a higher level of automation among its analytical functions. This need increases as staffing and training levels both decrease.        The program incorporates low level algorithms having data limitations on certain engine models. The program needs to incorporate more advanced algorithms to overcome data limitations on certain engine models.        The program has poor mid- to long-range planning capabilities. The program needs to improve the mid- to long-range planning capability to help flight operations.        
An example of CETADS' trending limitation is described as follows: Engine data obtained during take-off are compared to data collected from previous flights. Theoretically, a trend in this take-off data can be identified, and if this trend reaches a pre-set threshold, then a corresponding failure condition (or failure mode) can be inferred or signaled. Currently, the data trending functionality is compromised by data inconsistency due to the variation in flight conditions when the data are collected, and due to instrumentation uncertainties; consequently, false alarms and missed detections have reduced the credibility of CETADS' trending.
Another example of CETADS' limitations is mid- to long-range planning to help flight operations. Aside from scheduling routine repair/replacement of time/cycle-limited parts, CETADS provides little maintenance planning capability based on engine readiness or cost objective.
Thus, there is an increasing need for improved machinery and/or equipment health management and methods for accomplishing the same. This need for effective monitoring of machinery/condition and efficient maintenance planning is present for other industries as well.